Blank for cardboard box having a childproof lock system



FIG. 1 is a top perspective view thereof;

FIG. 2 is a front edge view thereof;

FIG. 3 is a rear edge view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side edge elevation view; and,

FIG. 7 is a right side edge elevation view thereof. 

CLAIM The ornamental designs for “blank for cardboard box having a childproof lock system”, as shown and described. 